Solid State to replace Audio Research REF110?

That's a tough one, if your a tube fan, as I am and probably you are too. I find it very hard to find a SS amp that has the speed matched to transparency and lack of grain you seem to get with tubes.

In my limited experience you need to go Class A in SS to get these charectaristics and I have always been a Pass fan, so I would say one of the Pass Class A amps or monoblocks, that meets your speakers power requirements. The only other SS amps that have really done it for me, are integrated amps, the Lavardin IT and Dartzeel integrated. Both had a lovely fast detailed sound without harshness.

Had the same problem with my ARC gear. Right now I'm using Ayre and would definitely recommend it. Pass is also good, but they don't sound anything like ARC.

Your problems are not due to having a tube amp but rather to having an Audio Research tube amp. If you do a little reading on the Agon forums, you will find many, many accounts similar to yours---a burst of sparks (if not actual flames) and a burned up resistor perhaps causing damage to the circuit board, all requiring an expensive trip back to the factory. In many of these accounts, this was the second or third time the customer had the problem.

For the life of me, I just don't see why anyone would put up with this. Other designs using the same output tubes are capable of far greater reliability and when an output tube does fail the only damage is a blown fuse that is easily replaced without the amp ever leaving home.

One example of a very good sounding tube amp that should be more reliable is the Emotive Audio Vita, which I happen to own. I have had zero problems during the 3 years I have owned the Vitas, but perhaps more importantly if I should have a catastrophic tube failure it should only pop a fuse, not take out other components. Plus there is no circuit board to be damaged. There are certainly many other good sounding yet reliable tube amps, but I mention the Emotive Vitas because Jonathan Valin of TAS had a pair in his system and said they were very similar in sound to the ARC 610T which was his reference at the time (this was around 2010). He also said the Vitas were the best medium power amps he had heard.

So don't give up on tubes. You just need to try a different brand.